The library began as a fork of an existing MIT-licensed library, and a number of inherited components remain part of the set. They are fully usable and documented alongside everything else.
As those components are rewritten or replaced with original implementations,
their attribution is tracked in THIRD_PARTY_NOTICES.md in the repository.
Removing a component from that file means it is now original to this project.
If you are upgrading from a very old copy, prefer the current component source in the docs: APIs have been tightened for accessibility and reduced motion. The update guide shows how to pull new versions without losing your edits.